Microtubular SnO2/V2O5 Composites Derived from Cellulose Substance as Cathode Materials of Lithium‐ion Batteries.

Abstract: Three‐dimensional microtubular SnO2/V2O5 composites with various SnO2 contents (2.2, 12.1 and 25.2 wt%) were fabricated by a facile sol−gel method employing natural cellulose substance (e. g., filter paper) as template. Thin VxOy/SnO2 gel layer was first deposited onto the surfaces of the cellulose microfibers of the filter paper through a dipping process, and then the as‐prepared VxOy/SnO2/cellulose composites were calcined in air to give the SnO2/V2O5 composites. The obtained composites inherit the morphology of the initial cellulose substance on the micrometer scale and consist of intricate microtubes composed of V2O5 nanorods with SnO2 nanoparticles anchored on the surfaces. Due to the unique three‐dimensional network structure of the composites and the synergetic effect of the V2O5 and SnO2 species, the SnO2/V2O5 composites displayed enhanced electrochemical performances when employed as cathode materials for lithium‐ion batteries. The composite with a SnO2 loading content of 12.1 wt% retained a stable discharge capacity of 126 mAh g−1 after 150 discharge/charge cycles at a current density of 0.1 A g−1. The three‐dimensional microtubular structure inherited from the cellulose substance improves the structural stability of the electrode materials and facilitates the diffusion of lithium ions, and the existence of SnO2 with an appropriate loading content enhances the conductivity of the composites. [ABSTRACT FROM AUTHOR]